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-rw-r--r--arch/x86/platform/olpc/olpc-xo1-sci.c629
1 files changed, 629 insertions, 0 deletions
diff --git a/arch/x86/platform/olpc/olpc-xo1-sci.c b/arch/x86/platform/olpc/olpc-xo1-sci.c
new file mode 100644
index 000000000..89f25af4b
--- /dev/null
+++ b/arch/x86/platform/olpc/olpc-xo1-sci.c
@@ -0,0 +1,629 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Support for OLPC XO-1 System Control Interrupts (SCI)
+ *
+ * Copyright (C) 2010 One Laptop per Child
+ * Copyright (C) 2006 Red Hat, Inc.
+ * Copyright (C) 2006 Advanced Micro Devices, Inc.
+ */
+
+#include <linux/cs5535.h>
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/pm_wakeup.h>
+#include <linux/power_supply.h>
+#include <linux/suspend.h>
+#include <linux/workqueue.h>
+#include <linux/olpc-ec.h>
+
+#include <asm/io.h>
+#include <asm/msr.h>
+#include <asm/olpc.h>
+
+#define DRV_NAME "olpc-xo1-sci"
+#define PFX DRV_NAME ": "
+
+static unsigned long acpi_base;
+static struct input_dev *power_button_idev;
+static struct input_dev *ebook_switch_idev;
+static struct input_dev *lid_switch_idev;
+
+static int sci_irq;
+
+static bool lid_open;
+static bool lid_inverted;
+static int lid_wake_mode;
+
+enum lid_wake_modes {
+ LID_WAKE_ALWAYS,
+ LID_WAKE_OPEN,
+ LID_WAKE_CLOSE,
+};
+
+static const char * const lid_wake_mode_names[] = {
+ [LID_WAKE_ALWAYS] = "always",
+ [LID_WAKE_OPEN] = "open",
+ [LID_WAKE_CLOSE] = "close",
+};
+
+static void battery_status_changed(void)
+{
+ struct power_supply *psy = power_supply_get_by_name("olpc_battery");
+
+ if (psy) {
+ power_supply_changed(psy);
+ power_supply_put(psy);
+ }
+}
+
+static void ac_status_changed(void)
+{
+ struct power_supply *psy = power_supply_get_by_name("olpc_ac");
+
+ if (psy) {
+ power_supply_changed(psy);
+ power_supply_put(psy);
+ }
+}
+
+/* Report current ebook switch state through input layer */
+static void send_ebook_state(void)
+{
+ unsigned char state;
+
+ if (olpc_ec_cmd(EC_READ_EB_MODE, NULL, 0, &state, 1)) {
+ pr_err(PFX "failed to get ebook state\n");
+ return;
+ }
+
+ if (test_bit(SW_TABLET_MODE, ebook_switch_idev->sw) == !!state)
+ return; /* Nothing new to report. */
+
+ input_report_switch(ebook_switch_idev, SW_TABLET_MODE, state);
+ input_sync(ebook_switch_idev);
+ pm_wakeup_event(&ebook_switch_idev->dev, 0);
+}
+
+static void flip_lid_inverter(void)
+{
+ /* gpio is high; invert so we'll get l->h event interrupt */
+ if (lid_inverted)
+ cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_INPUT_INVERT);
+ else
+ cs5535_gpio_set(OLPC_GPIO_LID, GPIO_INPUT_INVERT);
+ lid_inverted = !lid_inverted;
+}
+
+static void detect_lid_state(void)
+{
+ /*
+ * the edge detector hookup on the gpio inputs on the geode is
+ * odd, to say the least. See http://dev.laptop.org/ticket/5703
+ * for details, but in a nutshell: we don't use the edge
+ * detectors. instead, we make use of an anomaly: with the both
+ * edge detectors turned off, we still get an edge event on a
+ * positive edge transition. to take advantage of this, we use the
+ * front-end inverter to ensure that that's the edge we're always
+ * going to see next.
+ */
+
+ int state;
+
+ state = cs5535_gpio_isset(OLPC_GPIO_LID, GPIO_READ_BACK);
+ lid_open = !state ^ !lid_inverted; /* x ^^ y */
+ if (!state)
+ return;
+
+ flip_lid_inverter();
+}
+
+/* Report current lid switch state through input layer */
+static void send_lid_state(void)
+{
+ if (!!test_bit(SW_LID, lid_switch_idev->sw) == !lid_open)
+ return; /* Nothing new to report. */
+
+ input_report_switch(lid_switch_idev, SW_LID, !lid_open);
+ input_sync(lid_switch_idev);
+ pm_wakeup_event(&lid_switch_idev->dev, 0);
+}
+
+static ssize_t lid_wake_mode_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ const char *mode = lid_wake_mode_names[lid_wake_mode];
+ return sprintf(buf, "%s\n", mode);
+}
+static ssize_t lid_wake_mode_set(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ int i;
+ for (i = 0; i < ARRAY_SIZE(lid_wake_mode_names); i++) {
+ const char *mode = lid_wake_mode_names[i];
+ if (strlen(mode) != count || strncasecmp(mode, buf, count))
+ continue;
+
+ lid_wake_mode = i;
+ return count;
+ }
+ return -EINVAL;
+}
+static DEVICE_ATTR(lid_wake_mode, S_IWUSR | S_IRUGO, lid_wake_mode_show,
+ lid_wake_mode_set);
+
+static struct attribute *lid_attrs[] = {
+ &dev_attr_lid_wake_mode.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(lid);
+
+/*
+ * Process all items in the EC's SCI queue.
+ *
+ * This is handled in a workqueue because olpc_ec_cmd can be slow (and
+ * can even timeout).
+ *
+ * If propagate_events is false, the queue is drained without events being
+ * generated for the interrupts.
+ */
+static void process_sci_queue(bool propagate_events)
+{
+ int r;
+ u16 data;
+
+ do {
+ r = olpc_ec_sci_query(&data);
+ if (r || !data)
+ break;
+
+ pr_debug(PFX "SCI 0x%x received\n", data);
+
+ switch (data) {
+ case EC_SCI_SRC_BATERR:
+ case EC_SCI_SRC_BATSOC:
+ case EC_SCI_SRC_BATTERY:
+ case EC_SCI_SRC_BATCRIT:
+ battery_status_changed();
+ break;
+ case EC_SCI_SRC_ACPWR:
+ ac_status_changed();
+ break;
+ }
+
+ if (data == EC_SCI_SRC_EBOOK && propagate_events)
+ send_ebook_state();
+ } while (data);
+
+ if (r)
+ pr_err(PFX "Failed to clear SCI queue");
+}
+
+static void process_sci_queue_work(struct work_struct *work)
+{
+ process_sci_queue(true);
+}
+
+static DECLARE_WORK(sci_work, process_sci_queue_work);
+
+static irqreturn_t xo1_sci_intr(int irq, void *dev_id)
+{
+ struct platform_device *pdev = dev_id;
+ u32 sts;
+ u32 gpe;
+
+ sts = inl(acpi_base + CS5536_PM1_STS);
+ outl(sts | 0xffff, acpi_base + CS5536_PM1_STS);
+
+ gpe = inl(acpi_base + CS5536_PM_GPE0_STS);
+ outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS);
+
+ dev_dbg(&pdev->dev, "sts %x gpe %x\n", sts, gpe);
+
+ if (sts & CS5536_PWRBTN_FLAG) {
+ if (!(sts & CS5536_WAK_FLAG)) {
+ /* Only report power button input when it was pressed
+ * during regular operation (as opposed to when it
+ * was used to wake the system). */
+ input_report_key(power_button_idev, KEY_POWER, 1);
+ input_sync(power_button_idev);
+ input_report_key(power_button_idev, KEY_POWER, 0);
+ input_sync(power_button_idev);
+ }
+ /* Report the wakeup event in all cases. */
+ pm_wakeup_event(&power_button_idev->dev, 0);
+ }
+
+ if ((sts & (CS5536_RTC_FLAG | CS5536_WAK_FLAG)) ==
+ (CS5536_RTC_FLAG | CS5536_WAK_FLAG)) {
+ /* When the system is woken by the RTC alarm, report the
+ * event on the rtc device. */
+ struct device *rtc = bus_find_device_by_name(
+ &platform_bus_type, NULL, "rtc_cmos");
+ if (rtc) {
+ pm_wakeup_event(rtc, 0);
+ put_device(rtc);
+ }
+ }
+
+ if (gpe & CS5536_GPIOM7_PME_FLAG) { /* EC GPIO */
+ cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_NEGATIVE_EDGE_STS);
+ schedule_work(&sci_work);
+ }
+
+ cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS);
+ cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS);
+ detect_lid_state();
+ send_lid_state();
+
+ return IRQ_HANDLED;
+}
+
+static int xo1_sci_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ if (device_may_wakeup(&power_button_idev->dev))
+ olpc_xo1_pm_wakeup_set(CS5536_PM_PWRBTN);
+ else
+ olpc_xo1_pm_wakeup_clear(CS5536_PM_PWRBTN);
+
+ if (device_may_wakeup(&ebook_switch_idev->dev))
+ olpc_ec_wakeup_set(EC_SCI_SRC_EBOOK);
+ else
+ olpc_ec_wakeup_clear(EC_SCI_SRC_EBOOK);
+
+ if (!device_may_wakeup(&lid_switch_idev->dev)) {
+ cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE);
+ } else if ((lid_open && lid_wake_mode == LID_WAKE_OPEN) ||
+ (!lid_open && lid_wake_mode == LID_WAKE_CLOSE)) {
+ flip_lid_inverter();
+
+ /* we may have just caused an event */
+ cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS);
+ cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS);
+
+ cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE);
+ }
+
+ return 0;
+}
+
+static int xo1_sci_resume(struct platform_device *pdev)
+{
+ /*
+ * We don't know what may have happened while we were asleep.
+ * Reestablish our lid setup so we're sure to catch all transitions.
+ */
+ detect_lid_state();
+ send_lid_state();
+ cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE);
+
+ /* Enable all EC events */
+ olpc_ec_mask_write(EC_SCI_SRC_ALL);
+
+ /* Power/battery status might have changed too */
+ battery_status_changed();
+ ac_status_changed();
+ return 0;
+}
+
+static int setup_sci_interrupt(struct platform_device *pdev)
+{
+ u32 lo, hi;
+ u32 sts;
+ int r;
+
+ rdmsr(0x51400020, lo, hi);
+ sci_irq = (lo >> 20) & 15;
+
+ if (sci_irq) {
+ dev_info(&pdev->dev, "SCI is mapped to IRQ %d\n", sci_irq);
+ } else {
+ /* Zero means masked */
+ dev_info(&pdev->dev, "SCI unmapped. Mapping to IRQ 3\n");
+ sci_irq = 3;
+ lo |= 0x00300000;
+ wrmsrl(0x51400020, lo);
+ }
+
+ /* Select level triggered in PIC */
+ if (sci_irq < 8) {
+ lo = inb(CS5536_PIC_INT_SEL1);
+ lo |= 1 << sci_irq;
+ outb(lo, CS5536_PIC_INT_SEL1);
+ } else {
+ lo = inb(CS5536_PIC_INT_SEL2);
+ lo |= 1 << (sci_irq - 8);
+ outb(lo, CS5536_PIC_INT_SEL2);
+ }
+
+ /* Enable interesting SCI events, and clear pending interrupts */
+ sts = inl(acpi_base + CS5536_PM1_STS);
+ outl(((CS5536_PM_PWRBTN | CS5536_PM_RTC) << 16) | 0xffff,
+ acpi_base + CS5536_PM1_STS);
+
+ r = request_irq(sci_irq, xo1_sci_intr, 0, DRV_NAME, pdev);
+ if (r)
+ dev_err(&pdev->dev, "can't request interrupt\n");
+
+ return r;
+}
+
+static int setup_ec_sci(void)
+{
+ int r;
+
+ r = gpio_request(OLPC_GPIO_ECSCI, "OLPC-ECSCI");
+ if (r)
+ return r;
+
+ gpio_direction_input(OLPC_GPIO_ECSCI);
+
+ /* Clear pending EC SCI events */
+ cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_NEGATIVE_EDGE_STS);
+ cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_POSITIVE_EDGE_STS);
+
+ /*
+ * Enable EC SCI events, and map them to both a PME and the SCI
+ * interrupt.
+ *
+ * Ordinarily, in addition to functioning as GPIOs, Geode GPIOs can
+ * be mapped to regular interrupts *or* Geode-specific Power
+ * Management Events (PMEs) - events that bring the system out of
+ * suspend. In this case, we want both of those things - the system
+ * wakeup, *and* the ability to get an interrupt when an event occurs.
+ *
+ * To achieve this, we map the GPIO to a PME, and then we use one
+ * of the many generic knobs on the CS5535 PIC to additionally map the
+ * PME to the regular SCI interrupt line.
+ */
+ cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_EVENTS_ENABLE);
+
+ /* Set the SCI to cause a PME event on group 7 */
+ cs5535_gpio_setup_event(OLPC_GPIO_ECSCI, 7, 1);
+
+ /* And have group 7 also fire the SCI interrupt */
+ cs5535_pic_unreqz_select_high(7, sci_irq);
+
+ return 0;
+}
+
+static void free_ec_sci(void)
+{
+ gpio_free(OLPC_GPIO_ECSCI);
+}
+
+static int setup_lid_events(void)
+{
+ int r;
+
+ r = gpio_request(OLPC_GPIO_LID, "OLPC-LID");
+ if (r)
+ return r;
+
+ gpio_direction_input(OLPC_GPIO_LID);
+
+ cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_INPUT_INVERT);
+ lid_inverted = 0;
+
+ /* Clear edge detection and event enable for now */
+ cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE);
+ cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_EN);
+ cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_EN);
+ cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS);
+ cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS);
+
+ /* Set the LID to cause an PME event on group 6 */
+ cs5535_gpio_setup_event(OLPC_GPIO_LID, 6, 1);
+
+ /* Set PME group 6 to fire the SCI interrupt */
+ cs5535_gpio_set_irq(6, sci_irq);
+
+ /* Enable the event */
+ cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE);
+
+ return 0;
+}
+
+static void free_lid_events(void)
+{
+ gpio_free(OLPC_GPIO_LID);
+}
+
+static int setup_power_button(struct platform_device *pdev)
+{
+ int r;
+
+ power_button_idev = input_allocate_device();
+ if (!power_button_idev)
+ return -ENOMEM;
+
+ power_button_idev->name = "Power Button";
+ power_button_idev->phys = DRV_NAME "/input0";
+ set_bit(EV_KEY, power_button_idev->evbit);
+ set_bit(KEY_POWER, power_button_idev->keybit);
+
+ power_button_idev->dev.parent = &pdev->dev;
+ device_init_wakeup(&power_button_idev->dev, 1);
+
+ r = input_register_device(power_button_idev);
+ if (r) {
+ dev_err(&pdev->dev, "failed to register power button: %d\n", r);
+ input_free_device(power_button_idev);
+ }
+
+ return r;
+}
+
+static void free_power_button(void)
+{
+ input_unregister_device(power_button_idev);
+}
+
+static int setup_ebook_switch(struct platform_device *pdev)
+{
+ int r;
+
+ ebook_switch_idev = input_allocate_device();
+ if (!ebook_switch_idev)
+ return -ENOMEM;
+
+ ebook_switch_idev->name = "EBook Switch";
+ ebook_switch_idev->phys = DRV_NAME "/input1";
+ set_bit(EV_SW, ebook_switch_idev->evbit);
+ set_bit(SW_TABLET_MODE, ebook_switch_idev->swbit);
+
+ ebook_switch_idev->dev.parent = &pdev->dev;
+ device_set_wakeup_capable(&ebook_switch_idev->dev, true);
+
+ r = input_register_device(ebook_switch_idev);
+ if (r) {
+ dev_err(&pdev->dev, "failed to register ebook switch: %d\n", r);
+ input_free_device(ebook_switch_idev);
+ }
+
+ return r;
+}
+
+static void free_ebook_switch(void)
+{
+ input_unregister_device(ebook_switch_idev);
+}
+
+static int setup_lid_switch(struct platform_device *pdev)
+{
+ int r;
+
+ lid_switch_idev = input_allocate_device();
+ if (!lid_switch_idev)
+ return -ENOMEM;
+
+ lid_switch_idev->name = "Lid Switch";
+ lid_switch_idev->phys = DRV_NAME "/input2";
+ set_bit(EV_SW, lid_switch_idev->evbit);
+ set_bit(SW_LID, lid_switch_idev->swbit);
+
+ lid_switch_idev->dev.parent = &pdev->dev;
+ device_set_wakeup_capable(&lid_switch_idev->dev, true);
+
+ r = input_register_device(lid_switch_idev);
+ if (r) {
+ dev_err(&pdev->dev, "failed to register lid switch: %d\n", r);
+ goto err_register;
+ }
+
+ return 0;
+
+err_register:
+ input_free_device(lid_switch_idev);
+ return r;
+}
+
+static void free_lid_switch(void)
+{
+ input_unregister_device(lid_switch_idev);
+}
+
+static int xo1_sci_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ int r;
+
+ /* don't run on non-XOs */
+ if (!machine_is_olpc())
+ return -ENODEV;
+
+ res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "can't fetch device resource info\n");
+ return -EIO;
+ }
+ acpi_base = res->start;
+
+ r = setup_power_button(pdev);
+ if (r)
+ return r;
+
+ r = setup_ebook_switch(pdev);
+ if (r)
+ goto err_ebook;
+
+ r = setup_lid_switch(pdev);
+ if (r)
+ goto err_lid;
+
+ r = setup_lid_events();
+ if (r)
+ goto err_lidevt;
+
+ r = setup_ec_sci();
+ if (r)
+ goto err_ecsci;
+
+ /* Enable PME generation for EC-generated events */
+ outl(CS5536_GPIOM6_PME_EN | CS5536_GPIOM7_PME_EN,
+ acpi_base + CS5536_PM_GPE0_EN);
+
+ /* Clear pending events */
+ outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS);
+ process_sci_queue(false);
+
+ /* Initial sync */
+ send_ebook_state();
+ detect_lid_state();
+ send_lid_state();
+
+ r = setup_sci_interrupt(pdev);
+ if (r)
+ goto err_sci;
+
+ /* Enable all EC events */
+ olpc_ec_mask_write(EC_SCI_SRC_ALL);
+
+ return r;
+
+err_sci:
+ free_ec_sci();
+err_ecsci:
+ free_lid_events();
+err_lidevt:
+ free_lid_switch();
+err_lid:
+ free_ebook_switch();
+err_ebook:
+ free_power_button();
+ return r;
+}
+
+static int xo1_sci_remove(struct platform_device *pdev)
+{
+ free_irq(sci_irq, pdev);
+ cancel_work_sync(&sci_work);
+ free_ec_sci();
+ free_lid_events();
+ free_lid_switch();
+ free_ebook_switch();
+ free_power_button();
+ acpi_base = 0;
+ return 0;
+}
+
+static struct platform_driver xo1_sci_driver = {
+ .driver = {
+ .name = "olpc-xo1-sci-acpi",
+ .dev_groups = lid_groups,
+ },
+ .probe = xo1_sci_probe,
+ .remove = xo1_sci_remove,
+ .suspend = xo1_sci_suspend,
+ .resume = xo1_sci_resume,
+};
+
+static int __init xo1_sci_init(void)
+{
+ return platform_driver_register(&xo1_sci_driver);
+}
+arch_initcall(xo1_sci_init);